Examination of n - T9 conditions required by N = 50, 82, 126 waiting points in r-process

Nguyen Duy Ly,Nguyen Ngoc Duy,Nguyen Kim Uyen,Vinh N T Pham

Table 1. Two-neutron separation energies (S2n, in MeV) of the 76Fe, 77Co, 78Ni, 79Cu, 127Rh, 128Pd, 129Ag, 130Cd, 192Dy, 193Ho, 194Er, 195Tm critical waiting points (WPs) [(Z, A) nuclei], and their even-N neighbors [(Z, A + 2) nuclei]. The separation energy values calculated using the FRDM, WS4, DZ10, and KTUY models taken from [44, 46, 48, 49], respectively, are compared to available experimental data obtained from the AME2020 database [45]. The half-lives of the isotopes are taken from the NUBASE2020 database [52] or new QRPA calculations in [44].

WPs [44, 52] AME20 FRDM WS4 DZ10 KTUY AXN T1/2(ms) Z, A Z, A + 2 Z, A Z, A + 2 Z, A Z, A + 2 Z, A Z, A + 2 Z, A Z, A + 2 76Fe50 3.0 6.07 ± 0.78 2.90 ± 1.30 6.66 2.74 5.43 2.45 7.87 2.46 6.85 3.01 77Co50 15.0 7.49 ± 0.72 4.49 ± 1.16 7.41 3.59 7.23 3.32 8.74 3.48 7.94 3.79 78Ni50 122.2 8.83 ± 0.50 4.50 ± 0.72 8.58 4.43 8.83 4.26 9.48 4.45 9.33 4.45 79Cu50 241.3 9.69 ± 0.10 5.65 ± 0.32 9.60 5.56 9.66 5.64 10.00 5.58 10.15 5.61 127Rh82 28.0 8.04 ± 0.78 3.23 ± 1.15 9.15 3.55 7.96 3.68 8.66 4.05 8.80 3.89 128Pd82 35.0 8.74 ± 0.64 4.48 ± 0.58 9.49 4.38 8.62 4.31 9.16 4.68 9.48 4.48 129Ag82 49.9 9.36 ± 0.45 5.02 ± 0.64 10.17 5.00 9.41 4.90 9.70 5.22 10.13 5.12 130Cd82 126.8 10.02 ± 0.02 5.49 ± 0.06 10.87 5.60 10.23 5.47 10.46 5.63 10.80 5.68 192Dy126 0.02 N/A N/A 6.21 2.49 5.49 2.45 5.99 2.57 6.54 2.48 193Ho126 0.02 N/A N/A 6.54 2.97 5.75 3.07 6.48 3.05 6.97 3.52 194Er126 0.05 N/A N/A 6.97 3.39 6.02 3.60 6.97 3.52 7.47 3.34 195Tm126 0.04 N/A N/A 7.42 3.77 6.38 4.07 7.48 3.97 7.92 3.80